1. Field of the Invention
The present invention relates generally to inkjet printhead maintenance and, more particularly, to a method for detecting purging ink flow through printhead heater chip nozzles by firmware thermal analysis to enhance inkjet printhead maintenance.
2. Description of the Related Art
Thermal inkjet printers typically monitor the temperature of their printheads while printing. These printers can use a variety of temperature sensing methods to determine the temperature of any number of regions on the printheads. For example, as disclosed in the patent application cross-referenced above, many printers analyze the temperature by zone, where given zones are used to determine the temperature of a specific color or ink flow via.
Printheads can often be damaged, having degraded print quality, when air is ingested into their nozzles, vias and ink flow channels. Printheads can also show degraded print quality when their nozzles are clogged with dried ink or other contaminants. To manage both of these cases, and provide the ability to recover from these and other failures, printers will often implement a purge pump, typically taking the form of a peristaltic pump. The purge pump will attempt to draw or suction ink from the printhead nozzles in an attempt to clear the air or other clogs.
Another approach to printhead maintenance is to use a method of electrostatic detection of malfunctioning nozzles. This allows a determination of when maintenance operations need to be performed to improve the operational condition of the printhead nozzles. By using this method, the user is able to determine whether a purge cycle was successful in removing a clog, or if performing a second purge cycle is necessary.
Notwithstanding the existence of the aforementioned approaches, there is still a need for an innovation that will further enhance inkjet printhead maintenance.